1. Field of the Invention
The present invention relates to complex (multicomponent) functional microgels and compositions thereof as well as to a process for synthesizing said complex microgels in aqueous media.
A preferred embodiment of the invention relates to the synthesis of complex microgels, as such, to be used, among other things, as catalysts, carriers for immobilization of biologically active materials, fillers for plastics, filtration aids and ultrahigh-bulking pigments.
Another preferred embodiment of the invention relates to synthesizing, in situ, complex functional microgels in aqueous dispersions of particulate matter to provide improved and novel useful products through one or more of the following:
(a) instantaneous, indiscriminate and complete flocculation of said particulate matter;
(b) intrinsic cementation of the resultant particle aggregates; and
(c) surface-chemical modification of the resultant aggregate products.
The complex functional microgels of the present invention are synthesized by a rapid, virtually instantaneous cross-linking of in-situ-preformed transient, chemically reactive subcolloidal sodium-silico-aluminate and similar hydrosols with the aid of bivalent and/or multivalent inorganic salts and/or organic, cationically active chemical compounds with at least two reactive groups in each molecule.
2. Discussion of the Relevant Art
The related known art deals with monocomponent silica and bicomponent alumino-silicate systems in the form of gels, sols and precipitates, described by the general chemical formulas of [SiO.sub.2 ].sub.m, or [(SiO.sub.2).sub.m (Al.sub.2 O.sub.3).sub.n ].sub.p, where m, n and p represent arbitrary numbers. On the other hand, the complex microgels of the present invention, having at least three analogous components in their molecular make-up, have been hitherto unknown in the prior art to the best of the applicant's knowledge. In a most simple case, the complex microgels under discussion can be exemplified chemically by calcium-silico-aluminates, described by a general formula of [(CaO).sub.m (SiO.sub.2).sub.n (Al.sub.2 O.sub.3)].sub.n, where m, n, p and u represent arbitrary numbers.
To avoid potential confusion with regard to the subject matter under discussion, it is important to emphasize the fundamental difference between intrinsic multicomponent systems, such as the above-mentioned calcium-silico-aluminate microgels in which CaO, SiO.sub.2 and Al.sub.2 O.sub.3 are chemically bound within the same molecules, and analogous blended multicomponent systems exemplified by silicomagnesium-aluminate-hydrate gels disclosed by Hoffmann in U.S. Pat. No. 3,476,692. It should be pointed out, though, that calling Hoffmann's continuous gels silicomagnesium-aluminate-hydrates,, is misleading from the standpoint of chemical terminology in that, contrary to what the name implies, the latter are not indivisible chemical compounds (which cannot be separated into individual components without destroying the very compounds, as such) but are manufactured by first synthesizing a continuous silico-aluminate gel and, subsequently, precipitating a magnesium hydroxide in a chemically and colloidally already established continuous silico-aluminate gel.
It is also important to emphasize the distinction between the complex (multicomponent) microgels, e.g., those of the above-mentioned calcium-silico-aluminate type, on the one hand, and, for example, calcium-ion-loaded alumino-silicate (zeolite) cation exchangers, on the other. Whereas calcium is chemically bound within the calcium-silico-aluminate macromolecules making up the complex microgels under discussion, the alumino-silicate cation exchangers are fundamentally bicomponent chemical compounds of alumina and silica and remain invariably such bicomponent alumino-silicates regardless of which particular mobile bivalent or multivalent cations they may acquire by way of the reversible ion-exchange mechanism.
It should further be emphasized that no microgels, even of a simple monocomponent silica or bicomponent silico-aluminate type, had ever been demonstrated in the prior art to exist in the form of stable, permanent formations qualifying them as legitimate end products. Quite to the contrary, as shall be explained hereinafter it is fundamentally impossible to convert the relatively slowly forming, continuously changing silica or silico-aluminate microgels into such stable, permanently fixed formations (end products).
Although, to the best of the applicant's knowledge, there is a total lack of prior-art references pertaining directly to the subject matter of the present invention, even remotely related such references shall be discussed hereinafter whenever deemed useful to explaining the subject matter in question.
In accordance with the foregoing and disclosures to follow, the general object of the present invention is to provide a process and compositions for the manufacture of novel complex (multicomponent) functional microgels, which are useful as such or in conjunction with particulate matter.
More specifically, the object of the invention is to provide a process and compositions for synthesizing complex functional microgels in aqueous media by a rapid, virtually instantaneous, cross-linking of in-situ-preformed transient, chemically reactive subcolloidal silico-aluminate and similar hydrosols with the aid of bivalent (multivalent) inorganic salts and/or organic, cationically active chemical compounds with at least two reactive groups in each molecule.
A yet more specific object of the invention is to provide a process and compositions for the manufacture of complex functional microgels to be used, among other things, as catalysts (activators, inhibitors), carriers for immobilization of biologically active materials, fillers for plastics, filtration aids and ultrahigh-bulking pigments.
A yet another specific object of the invention is to provide a process and compositions for synthesizing, in situ, complex functional microgels in aqueous dispersions of particulate matter, such as mineral and/or synthetic particulates and/or fibers, to flocculate said particulate matter instantaneously, indiscriminately and completely and then intrinsically cement the resultant aggregates to yield improved and novel products.
A still further object of the invention is to provide a process and compositions for synthesizing, in-situ, complex functional microgels in aqueous dispersions of particulate matter to impart an intrinsic, dual steric matrix of hydrophilic and organophilic sites to the resultant aggregate formations, thus rendering them compatible with (wettable by) both polar and nonpolar media.